EAU CLAIRE, Wis. (WEAU) – What goes down, must go down some more and eventually through the wastewater treatment plant. In the city of Eau Claire, the sewage is going “green.”
A multi-million dollar wastewater energy project is underway and it comes just in time for Green Week, hosted by the city’s Green Team. Each day this week, the city is focusing on energy, purchasing, travel, water or recycling.
By year 2025, the city wants to obtain 25 percent renewable energy and its well on its way toward the goal thanks to green initiatives like the wastewater treatment plant’s energy project.
Jeff Pippenger is the utilities administrator for the city’s wastewater treatment plant.
“We handle all the wastewater for the city of Eau Claire, city of Altoona and town of Washington sanitary sewer district,” said Pippenger. “Basically anything that goes down a drain, down a toilet, through a tub, comes here and we treat it here before it goes into the receiving water which is the Chippewa River.”
5.6 million gallons of wastewater come through the facility each day. That’s about 2 billion gallons in a year. It undergoes primary treatment where debris and particles are removed from the wastewater to prepare for the biological treatment process. In-organics like sand and gravel are also removed in the process.
Kathryn White, an assistant chemist for the city, said natural microorganisms in the wastewater will eat away at the organic material or “sludge”, cleaning the water. White and a lab technician test the water seven days a week, 365 days a year, to meet compliance and regulatory procedures.
After the wastewater is cleaned, the effluent is then released into the Chippewa River, with no harmful chemicals or toxins.
“We actually digest our bio-solids which actually produce a methane gas and we utilize that gas to produce energy,” said Pippenger.
The $39.4 million project at the wastewater treatment site will make improvements from 1980. Pippenger said the motors from 34 years ago need an upgrade which will be much more energy efficient.
“We've got a lot of big motors that run the pumps in the facility. We're going to be upgrading those to more efficient models. More than that, we're going to be putting VFD’s, variable frequency drives, on the motors that will be make it more efficient to operate those motors,” said Pippenger.
He said with the methane generation from the two new biofuel generators will likely pay them off in six years, a $1.3 million.
There will also be improvements inside the plant. LED lights that are motion censored will help save money. White said the wastewater treatment lab will be remodeled to be more ergonomic.
Inside the lab, White does a variety of testing, measuring the solids in the water, organic content and other chemical levels.
“We have a microscope where we can verify the bacteria in the water and the efficiency of the treatment, so we're going to be using this a lot more in our new plant,” said White.
The plant will also save on heat, thanks to the two new biofuel generators.
“We're going to be capturing the heat exhaust off those and we're going to be able to save 50 percent of the heating of our facility when those are in operation,” said Pippenger.
Another 20 percent of heating will be saved because energy will be captured from the treated wastewater, which sits at 50 degrees almost year round.
The sludge that’s removed from the wastewater is given to farmers. Pippenger said 3,000 acres of the sludge will be used on farmland to bring nutrients into the ground.